Improvements in, or relating to, methods and apparatus for securing two different lengths of path of the slurcock, and driving heads of the thread guides on a cotton knitting machine

摘要

686,523. Knitting-machines. BATA, NARODNI PODNIK. May 3, 1948. [May 8, 1947] No. 12062/48. Class 74 (ii). In a cotton machine, to vary the throw of the draw lever and so to change from one to the other of two different lengths of path of the slurcock and of the thread guide driving heads, a slide block, which transmits the drive to the draw lever, is displaced from one end position to the other in a guide slot in the draw lever, during the sinking of a single course of loops, by a member forming part of the draw mechanism. The lever 18 driving the slurcock 29 is oscillated by a slide 8, reciprocated, with a dwell at the end of each stroke, by a cam 1 driven at half main cam-shaft speed. The slide is coupled to the lever by relatively rotatable blocks 14, 16 working in slots 13, 17 in slide and lever. The block 14 carries a rack 31 by which a pinion 32, borne on the slide 8, can raise or lower both blocks, to vary the stroke of the lever. The pinion 32 is fast with a pinion 34 engaging a rack 35 slidable along the slide 8, but locatable in alternative positions by a spring-pressed detent 51 on the slide 8. A bar 42, slidable along the rack 35, carries a ramp 43 which can act on inclined faces 52 on the detent to release it. Towards the end of a stroke, the bar 42 is arrested by engagement of an adjustable abutment 44 thereon with a tooth on an abutment disc 58. The rack 35 moves on until it is released from the slide 8 by the ramp 43 and is arrested by engagement of an adjustable abutment 38 which it carries with the tooth on the disc 58. Thereupon the pinion 34 rolls along the rack 35 causing the blocks 14, 16 to be moved along their slots to their other position, in which they are secured by location of the rack 35 in its alternative position by the detent 51. The abutment discs 58 are located, with their teeth in staggered relationship, on a shaft 57 which is racked round half a tooth pitch at a time, from a control drum, during the dwell of the slurcock. The movement of the blocks 14, 16 occurs during the sinking of a single course of loops. The draw lever 18 drives the slurcock 29, through a gear sector 20, pinions 21, 22, 24 and a worm 27 engaging small rollers 28 on the slurcock.